Malicious PDF — malware analysis report

Static analysis result for SHA-256 a2957d48785caeee…

MALICIOUS

PDF

33.1 KB Created: 2020-08-30 05:49:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: c636670e1c915c7c664913089e18be26 SHA-1: 72fd300ccaf6b4768870c51ad4d74c9151ef1441 SHA-256: a2957d48785caeee9cda63b031561f99d995b35c6baa8efdba65e5b52c27887f
152 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains a critical heuristic firing for a malicious redirector link, which is also present in the document body. This link, 'https://ttraff.cc/wix?keyword=principles+of+microeconomics+chapter+16+answers', is designed to lure users into clicking on what appears to be academic content. The PDF also exhibits characteristics of a link farm, with numerous embedded links, many pointing to Shopify-hosted PDFs. The ML classifier strongly indicates maliciousness.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 4

  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://ttraff.cc/wix?keyword=principles+of+microeconomics+chapter+16+answers
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/78394199391.pdf
    • https://cdn.shopify.com/s/files/1/0454/5862/0574/files/bugamaduwozodalovedimu.pdf
    • https://cdn.shopify.com/s/files/1/0433/3905/5258/files/33229320354.pdf
    • https://cdn.shopify.com/s/files/1/0430/9070/6599/files/28581724670.pdf
    • https://cdn.shopify.com/s/files/1/0433/3689/2584/files/sumozuwikamuwejaxuxa.pdf
    • https://static.usrfiles.com/ugd/b8c837_869ea1663a48477aac062d4ac3bcb323.pdf
    • https://static.usrfiles.com/ugd/b8c837_b0982783c8a74a7fbd26e7c57e3af696.pdf
    • https://cdn.shopify.com/s/files/1/0459/1216/2453/files/video_helper_7_license_key.pdf
    • https://cdn.shopify.com/s/files/1/0437/4672/1946/files/nawesu.pdf
    • https://cdn.shopify.com/s/files/1/0440/1925/3413/files/63239569237.pdf
    • https://cdn.shopify.com/s/files/1/0438/7454/9928/files/34631685674.pdf
    • https://cdn.shopify.com/s/files/1/0436/1738/6659/files/microsoft_office_2007_indir_cretsiz.pdf
    • https://static.usrfiles.com/ugd/3bf302_c771fd6f8eba469c86b7e8c3619e1040.pdf
    • https://static.usrfiles.com/ugd/daca0d_3b80bf8addb44a169a9f8748ad3fade2.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000444a.bin
872d4d07b9df3db9e1c3f015b28f5ea2ef45730f718816b6035cb4c7b405e87c
pdf-font-stream PDF embedded font (sfnt) at offset 0x444A 5556 bytes
font_01_sfnt_off00005711.bin
083dcd1b809ad732d39e0067a7b303469ddc7f945ba450ca1424ebff5cbecdaf
pdf-font-stream PDF embedded font (sfnt) at offset 0x5711 9564 bytes